Diagnostic test stick



FIG. 1 is a front elevation view of a diagnostic test stick in accordance with the present design;

FIG. 2 is a right side elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a front perspective view thereof; and,

FIG. 8 is a rear perspective view thereof.

The broken lines in FIG. 6 depict portions of the diagnostic test stick that form no part of the claimed design. 

CLAIM The ornamental design for a diagnostic test stick, as shown and described. 